JP2016219622A - Light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device that can increase the angle of field by enlarging a pixel space without increasing the number of light emitting elements.SOLUTION: A plurality of light receiving elements 2 constituting a light receiving device 1 are arranged in each of a matrix arrangement region 1a and checkered arrangement regions 1b, 1c. A power supply line 4 for power supply is wired from a control circuit 3 to the light receiving element 2 positioned in a column direction. Since the number of light receiving elements 2 is reduced in the checkered arrangement areas 1b, 1c, the power supply line 4 is not required to be configured in a thicker pattern than necessary, and can be arranged so as to be overlapped with a light receiving circuit 2b of the light receiving element 2. Accordingly, the light receiving portions 2a of the light receiving elements 2 can be densely arranged without providing any arrangement gap therebetween. Although element-absent pixels are generated, pixel information can be generated by using light reception information of element-present pixels according to interpolation processing.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light receiving device.

  As a light receiving device used for a camera or LIDAR (laser imaging detection and ranging; laser radar), for example, there is one in which a large number of light receiving elements are arranged in a matrix. In such a light receiving device, it is required to increase the degree of integration of the light receiving elements in order to obtain information with higher accuracy when generating an image from a light receiving signal.

  However, as the number of light receiving elements increases, the number of light receiving elements connected to the power supply wiring also increases. Accordingly, it is necessary to increase the thickness of the power supply wiring in order to supply necessary power to each light receiving element. However, when the power supply wiring becomes thicker, it becomes difficult to arrange a light receiving element in that portion, and it becomes difficult to increase the degree of integration. For this reason, there is a limit to the number of elements arranged per light-receiving surface, which hinders an increase in sensitivity. As a result, there is a limit in that the viewing angle cannot be widened.

JP 2014-529923 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a light receiving device capable of expanding the pixel space and widening the viewing angle without increasing the number of light receiving elements. It is in.

  The light-receiving device according to claim 1 is provided with a light-receiving unit and a light-receiving signal processing circuit, and is arranged in a first direction among the plurality of light-receiving elements arranged two-dimensionally in the arrangement region. A power line disposed at a position excluding at least the light receiving portion, and at least a part of the plurality of light receiving elements in the arrangement region is in a checkered pattern. A checkered arrangement area is provided.

  By adopting the above configuration, it is possible to halve the number of light receiving elements in the checkered arrangement region, and it is possible to obtain a light receiving signal from a wide range without making the power line a thick pattern. Without increasing the number, the pixel space can be enlarged to widen the viewing angle.

Schematic plan view of the light receiving device showing the first embodiment Action explanatory view showing the second embodiment Explanatory drawing of the signal processing which shows 3rd Embodiment Action explanatory diagram showing the fourth embodiment Schematic plan view of a light receiving device showing a fifth embodiment Schematic plan view of a light receiving device showing a sixth embodiment Illustration of signal processing (1) Illustration of signal processing (2) Two action explanatory views showing the seventh embodiment Action explanatory diagram showing the eighth embodiment

(First embodiment)
Hereinafter, a first embodiment when the present invention is used in a light receiving device of a laser radar (LIDAR) provided in a vehicle will be described with reference to FIG.

  The laser radar irradiates and scans laser light forward from a light emitting unit with a light emitting element such as a semiconductor laser, and obtains a difference in light reception time from the irradiation timing of the reflected light, and determines the object light according to the scanning position of laser light irradiation. The distance is detected. In this case, the distance of the object ahead is detected two-dimensionally by scanning the laser beam two-dimensionally. In addition, laser light irradiation is performed a plurality of times on the same position, a histogram is created by dividing the obtained light reception time difference values, and the distance is calculated based on the most frequently received light reception time difference data. I have to.

  In such a laser radar, the light receiving device 1 is provided with a plurality of light receiving elements 2 so as to receive reflected light from the direction in which the laser light is irradiated, and the distance information received by these light receiving elements 2 is provided in front of the distance information. Information such as an obstacle is created as pixel information.

  Next, the configuration of the light receiving device 1 having such a function will be described with reference to FIG. The light receiving device 1 includes a plurality of light receiving elements 2 and a control circuit 3 that performs signal processing of these received light signals. Each light receiving element 2 includes a light receiving portion 2a and a light receiving circuit 2b. The light receiving circuit 2b is provided for each light receiving element 2, and performs signal processing such as amplifying a light receiving signal from the light receiving unit 2a. The control circuit 3 functions as a pixel information processing unit.

  The light receiving surface of the light receiving device 1 is provided with a matrix arrangement area 1a in which the light receiving elements 2 are densely arranged and checkered arrangement areas 1b and 1c in which the light receiving elements 2 are arranged in a checkered pattern. In this case, the checkered arrangement areas 1b and 1c are provided separately above and below the matrix arrangement area 1a.

  This is because, for example, as a detection target area for projecting laser light, the matrix arrangement area 1a corresponds to the central portion in front of the road, the lower checkered arrangement area 1b corresponds to the closest distance in front of the road, and the upper checkerboard. The arrangement area 1c corresponds to the upper part from the road ahead. In this configuration, by providing the matrix arrangement area 1a in the center, it is possible to cover an area that requires detailed information.

  The light receiving elements 2 in the matrix arrangement region 1a are arranged so as to be aligned in the row direction and the column direction, and adjacent ones are provided in a dense state. In the checkered arrangement regions 1b and 1c, the light receiving elements 2 are arranged with every other lattice point in each of the row direction and the column direction. That is, the arrangement density of the light receiving elements 2 is reduced to ½.

  The control circuit 3 is provided on one end side of the region where the light receiving element 2 is disposed. Further, a power line 4 for supplying an operating power to each light receiving element 2 is provided for each column and is led to the control circuit 3. In this case, since the number of the light receiving elements 2 provided in each column is half of the checkered arrangement areas 1b and 1c, the power supply line 4 can reduce the voltage drop due to the power supply, so that all the matrix arrangement areas are used. It can be provided with a relatively thin wiring pattern having a smaller current capacity than the case.

  Each light receiving element 2 is provided with a signal line (not shown) for taking a received light signal into the control circuit 3. The light reception signal of each light receiving element 2 input via the signal line is subjected to signal processing in the control circuit 3 and is two-dimensionally in a state in which the distance to the front object is associated with the arrangement position of the light receiving element 2. Detected.

  According to the first embodiment, the light receiving device 1 includes the matrix arrangement area 1a in which the light receiving elements 2 are densely arranged in a matrix and the checkered arrangement areas 1b and 1c in which the light receiving elements 2 are arranged in a checkered pattern. The configuration. As a result, the current capacity of the power supply line 4 provided from the control circuit 3 to the light receiving elements 2 in each column can be suppressed, so that a wide pattern can be avoided and the light receiving circuit 2b of the light receiving element 2 can be avoided. It can be arranged on the top or in a narrow part between the light receiving elements 2. Therefore, it is possible to provide the light receiving device 1 in which a large number of light receiving elements 2 are arranged and the viewing angle is widened as a whole without causing a region where the light receiving elements 2 cannot be arranged due to the power supply line 4.

In this embodiment, the matrix arrangement area 1a is arranged as an area where pixel information is densely required, and the checkerboard arrangement areas 1b and 1c are allocated to areas where the pixel information is sufficient, so that it is practical. It is effective.
In addition, when it is better to make pixel information dense as a whole, continuous pixel information is generated by generating pixel information by performing an interpolation process or the like corresponding to a non-element pixel in which no light receiving element is arranged. Can be obtained.

In the above-described embodiment, the checkered arrangement regions 1b and 1c are provided. However, only one of them may be provided. It is also possible to arrange the checkerboard arrangement area 1b at the center and the matrix arrangement area 1a above and below it.
Although the checkered arrangement regions 1b and 1c are provided in units of a plurality of rows, they may be provided in units of a plurality of columns. Furthermore, the light receiving surface of the light receiving device 1 can be divided into blocks, and can be set as a matrix arrangement area and a checkered arrangement area for each block.

(Second Embodiment)
FIG. 2 shows the second embodiment. Hereinafter, parts different from the first embodiment will be described. In the first embodiment, since the light receiving elements 2 are arranged in a checkered pattern in the checkered arrangement regions 1b and 1c of the light receiving device 1, the image becomes rough. In this embodiment, in order to process this as an image having a smooth change, information about an element pixel that is a pixel in which the light receiving element 2 is disposed is used for an elementless pixel in which the light receiving element 2 is not disposed. Also, the pixel information is generated by an interpolation process as described below.

  In this case, as shown in FIG. 2, the non-element pixel to be subjected to the interpolation process is A, and pixel information is set to the left side for the element pixel a that is adjacent to the upper and lower sides (adjacent with the inter-pixel distance “1”). To a (1) to a (4) in a counterclockwise direction. Similarly, pixel information is sequentially set to b (1) to b (8) for the element pixel b that is adjacent on the outside (adjacent with an inter-pixel distance “√5”).

  In addition, although it cannot be used by direct reference, if it is assumed that interpolation processing is performed a plurality of times, the pixel information of the non-element pixels B and C once generated by the interpolation processing can also be used. . In this case, B (1) to B (4) are pixel information generation results of the non-element pixel B adjacent in the oblique direction around the no-element pixel A (adjacent with the inter-pixel distance “√2”). . Similarly, C (1) to C (4) are pixel information generation results of the non-element pixels C that are further adjacent in the vertical direction outside (adjacent at an inter-pixel distance “2”).

Next, the interpolation process will be specifically described.
[A] When the pixel information a (1) to a (4) and b (1) to b (8) such as the element pixels a and b are directly referred to as the interpolation processing of the elementless pixel A, for example, The following two methods can be used.

[A-1] The pixel information A of the non-element pixel A is interpolated with the pixel information a (1) to a (4) of the element pixel having the inter-pixel distance “1”.
At this time, weighting coefficients k1 to k4 for adding pixel information are set. When the pixel information is referred to evenly, k1 to k4 = 0.25 can be set. Also, different values can be set when changing the weight depending on the location. Further, the sum of these weighting coefficients is set to “1”. The pixel information A of the non-element pixel A can be obtained by the following equation (1).
A = k1 * a (1) + k2 * a (2) + k3 * a (3) + k4 * a (4) (1)

[A-2] The pixel information A of the non-element pixel A is changed from the pixel information a (1) to a (4), b (1) to b () of the element pixel having the inter-pixel distances “1” and “√5”. 8) Interpolate.
Here, the weighting coefficients of the pixel information a (1) to a (4) of the element pixel a having the inter-pixel distance “1” are k1 to k4. Further, the weighting coefficients of the pixel information b (1) to b (8) of the element pixel b with the inter-pixel distance “√5” are m1 to m8. However, the sum of the weighting coefficients k1 to k4 and m1 to m8 is “1”. The pixel information A of the non-element pixel A can be obtained by the following equation (2).
A = k1 * a (1) + k2 * a (2) + k3 * a (3) + k4 * a (4)
+ M1 * b (1) + m2 * b (2) + m3 * b (3) + m4 * b (4)
+ M5 × b (5) + m6 × b (6) + m7 × b (7) + m8 × b (8) (2)

[B] When the pixel information a (1) to a (4) of the elemental pixel a and the pixel information B (1) to B (4) of the elementless pixel B are referred to as the interpolation processing of the elementless pixel A For example, the following two methods can be used. In this case, since pixel information of non-element pixels does not exist in the first interpolation process, pixel information is generated by performing the above-described interpolation process [1] as the first interpolation process, for example. Thereafter, the interpolation process is performed indirectly using the pixel information of the non-element pixel as the second and subsequent interpolation processes.

[B-1] The pixel information of the non-element pixel A is the pixel information a (1) to a (4) of the element pixel having the inter-pixel distance “1” and the non-element pixel B of the inter-pixel distance “√2”. Interpolation is performed using the pixel information B (1) to B (4).
At this time, weighting coefficients k1 to k4 and K1 to K4 for adding pixel information are set. The sum of these weighting coefficients k1 to k4 and K1 to K4 is set to be “1”. The pixel information A of the non-element pixel A can be obtained by the following equation (3).
A = k1 * a (1) + k2 * a (2) + k3 * a (3) + k4 * a (4)
+ K1 * B (1) + K2 * B (2) + K3 * B (3) + K4 * B (4) (3)

[B-2] The pixel information A of the non-element pixel A is changed from the pixel information a (1) to a (4) of the element pixel a having the inter-pixel distance “1”, the inter-pixel distance “√2”, and the inter-pixel distance. Interpolation is performed using pixel information B (1) to B (4) and C (1) to C (4) of the elementless pixels B and C of “2”.
At this time, weighting coefficients k1 to k4, K1 to K4, and M1 to M4 for adding pixel information are set. The sum of these weighting coefficients k1 to k4, K1 to K4, and M1 to M4 is set to “1”. The pixel information A of the non-element pixel A can be obtained by the following equation (4).
A = k1 * a (1) + k2 * a (2) + k3 * a (3) + k4 * a (4)
+ K1 × B (1) + K2 × B (2) + K3 × B (3) + K4 × B (4)
+ M1 * C (1) + M2 * C (2) + M3 * C (3) + M4 * C (4) (4)

  According to the second embodiment, pixel information is generated for the non-element pixels A in the checkered arrangement areas 1b and 1c using the pixel information of the surrounding element elements, so that the pixels equivalent to the matrix arrangement area 1a are generated. Information can be obtained.

  In the above description, two examples are shown for each of [A] for direct reference and [B] for indirect reference. However, pixel information of elemental pixels adjacent to the outer periphery or pixel of non-elemental pixels. Interpolation processing can also be performed using information.

(Third embodiment)
FIG. 3 shows a third embodiment. In this embodiment, the process of the received light signal by the light receiving element 2 performed in the first embodiment described above and the specific process in the case of performing the interpolation process in the second embodiment are shown. The contents of signal processing performed by the control circuit 3 are shown. The following processing steps can be executed by the control circuit 3 in a CPU such as a microcomputer by a program, or can be executed by a hardware circuit combined with a logic circuit.

  FIG. 3A shows a process of processing signals received by the respective light receiving elements 2 in the matrix arrangement area 1a or the checkered arrangement areas 1b and 1c of the light receiving device 1. First, the control circuit 3 calculates the time difference between the light emission timing of the laser light from the light emitting unit and the light reception timing of the light reception signal by the light receiving element 2 by time digital conversion. The calculated time information is a time from when the laser beam is projected until the object is reflected by the object and received, that is, a time of flight (ToF). Since this flight time corresponds to the distance traveled by light, it is equivalent to a value obtained by doubling the distance to the object.

  Laser light irradiation is performed a plurality of times in the same direction, and a plurality of pieces of flight time information can be obtained. The control circuit 3 counts these flight time information for each section and generates a histogram. Subsequently, the control circuit 3 calculates a distance corresponding to the flight time of the section by selecting a section having the highest appearance frequency in the histogram section from the flight time obtained by the multiple times of laser light irradiation. And determine the distance to the object. Information on the distance value obtained as a result is output as pixel information. By performing the above processing on the light reception signals of all the light receiving elements 2, it is possible to obtain distance value information two-dimensionally and display it as an image.

  Next, a basic processing method of the interpolation processing shown in the second embodiment will be described with reference to FIG. As described above, in the processing of the light reception signal of the light receiving element 2 by the control circuit 3, the distance value is calculated by a histogram in which the time of flight obtained by a plurality of times of laser irradiation is divided. The pixel information of the non-element pixel can be generated by performing the interpolation processing shown in the second embodiment on the distance value itself of the calculation result.

  In this embodiment, an example will be described in which the control circuit 3 performs an interpolation process in the course of generating the above-described histogram. That is, instead of using the result of calculating the distance value for the element pixel, the control circuit 3 adds the histogram itself generated in the distance value calculation process by multiplying by the weighting coefficient, and generates the histogram for the non-element pixel A. .

The control circuit 3 calculates a distance based on the histogram of the non-element pixel A to calculate a distance value to the object.
Note that the interpolation process can be executed a plurality of times as described above, so that it can also be used as information when interpolation is performed for non-element pixels.
Also according to the third embodiment, the same effects as those of the first embodiment or the second embodiment can be obtained.

(Fourth embodiment)
FIG. 4 shows a fourth embodiment. In this embodiment, the laser beam L emitted from the light emitting unit is set so as to spread vertically as shown in the figure. For example, in this embodiment, the laser light L is spread so as to correspond to the pixels for one column in the vertical direction. In this case, in the spread laser beam L, the intensity changes at the center portion and the upper and lower end portions of the light spot as shown in the distribution diagram of the laser beam intensity on the right side of the drawing.

As a result, the level of the received light signal is highest at the upper and lower intermediate positions of the light receiving unit, and the level of the received light signal is lowered at the upper and lower ends. In such a case, when the pixel information of the non-element pixel A is obtained by interpolation processing, a difference corresponding to the light reception level may be set as the weighting coefficient. For example, when using the interpolation processing formula (1) shown in the second embodiment for the non-element pixel A as shown in the drawing, the weighting coefficients k1 to k4 satisfy the magnitude relationship as in the following formula (5). It is good to set as follows.
A = k1 * a (1) + k2 * a (2) + k3 * a (3) + k4 * a (4) (1)
k2> k1 = k3> k4 (5)

  According to the fourth embodiment as described above, since the weighting coefficient for performing the interpolation process is set according to the intensity of the laser light L from the light emitting unit, more accurate pixel information can be generated. become.

(Fifth embodiment)
FIG. 5 shows a fifth embodiment. Hereinafter, parts different from the fourth embodiment will be described. In this embodiment, the configuration of the light receiving device 11 in the case of irradiating the laser beam L by the light emitting unit as shown in the fourth embodiment is shown. In this configuration, the light receiving device 11 has light receiving elements 12 arranged in a matrix. Alternatively, it is also possible to target an arrangement in which the light receiving elements 12 are arranged in a checkered pattern with respect to the matrix pixels of the light receiving device 11.

  As described above, the laser light L emitted from the light emitting unit is emitted forward of the vehicle as a beam that spreads up and down. Therefore, like the laser light intensity distribution shown in the right part of FIG. 5, the intensity of the laser light L is strong in the central portion and has an intensity distribution that changes to weak intensity as it moves up and down. In the fourth embodiment, the weighting coefficient is adjusted when performing the interpolation process corresponding to such a case. In this embodiment, the area of the light receiving portion of the light receiving element 12 is configured to be different so that the received light amount is equal even when the intensity of the laser light L is reduced.

  As shown in FIG. 5, the light receiving elements 12 are arranged in a matrix on the light receiving surface of the light receiving device 11. For the purpose of explanation, for example, an example of arrangement in 7 rows and 9 columns is shown. Each light receiving element 12 is given a subscript expressed in a matrix. For example, the light receiving element 12 (1, 1) is shown as being arranged in 1 row and 1 column, and the light receiving element 12 (7, 5) is shown as being arranged in 7 rows and 5 columns.

  The laser beam L is irradiated a plurality of times at the same position along the center line C of the light receiving device 11, and then moved in the horizontal direction, that is, in the row direction, and the irradiation is repeated again. As a result, the light receiving elements 12 (4, 1) to 12 (4, 9) in the fourth row corresponding to the center position of the light receiving device 11 have the strongest laser light intensity. The light receiving elements 12 (1, 1) to 12 (1, 9) in the first row of the upper end row and the light receiving elements 12 (7, 1) to 12 (7, 9) in the seventh row of the lower end row are the most. It becomes weak laser beam intensity.

  In this embodiment, the light receiving area of the light receiving elements 12 (4, 1) to 12 (4, 9) in the fourth line of the center line C is set to be the smallest in correspondence with such a laser intensity distribution. Yes. In addition, the light receiving area of the light receiving element 12 shifted in the vertical direction is set to gradually increase. Thereby, each light receiving element 12 becomes equivalent in received light amount corresponding to the intensity of the laser beam.

  As a result, the light reception signal of the light receiving element 12 can be used as it is without correcting the light reception signal in accordance with the intensity distribution of the laser light L, and the signal processing can be simplified and a rapid detection process can be performed.

  Also in the fifth embodiment, when the light receiving elements 12 are arranged in a checkered pattern, the second embodiment or the third embodiment is used when the light receiving information of the non-element pixels is calculated by interpolation processing. It can be obtained in the same way.

(Sixth embodiment)
FIGS. 6 to 8 show the sixth embodiment, and only the parts different from the fifth embodiment will be described below. In this embodiment, as shown in FIG. 6, instead of changing the area of the light receiving portion of the light receiving element in accordance with the intensity of the laser light, the area is changed by arranging the light receiving elements having the same area of the light receiving portion. Instead, the same effect is obtained by performing signal processing for one light receiving element.

  As shown in FIG. 6, the light receiving elements 13 are arranged in a matrix on the light receiving surface of the light receiving device 11a. For the purpose of explanation, for example, an arrangement in 11 rows and 4 columns is shown. Each light receiving element 13 is given a subscript expressed in a matrix. For example, the light receiving element 13 (1, 1) is shown as being arranged in 1 row and 1 column, and the light receiving element 13 (11, 4) is shown as being arranged in 11 rows and 4 columns.

  Since the laser light L moves in the horizontal direction, that is, in the row direction every time it is irradiated a plurality of times along the center line C of the light receiving device 11 a, the light receiving elements 13 in the sixth row corresponding to the center position of the light receiving device 11. (6, 1) to 13 (6, 4) have the strongest laser light intensity. The light receiving elements 13 (1, 1) to 13 (1, 4) in the first row in the upper end row and the light receiving elements 13 (11, 1) to 13 (11, 4) in the eleventh row in the lower end row are the most. It becomes weak laser beam intensity.

  In this embodiment, unlike the fifth embodiment, the light receiving area of the light receiving element 13 is not set differently. Instead, signal processing is performed as follows. First, the light receiving elements 13 (6, 1) to 13 (6, 4) in the sixth row located on the center line C use the light receiving signals as they are. The light receiving elements 13 in the 5th and 7th rows adjacent to the light receiving elements 13 in the 6th row are combined with the light receiving elements 13 in the 4th and 8th rows that are further adjacent to each other. The received light signal is used. Furthermore, for the light receiving elements 13 adjacent in the vertical direction, the light reception signals of the light receiving elements 13 for three rows are used.

  As a result, a plurality of light receiving elements 13 are provided corresponding to the intensity of the laser beam L that is lowered apart from the center line C without correcting the received light signal according to the intensity distribution of the laser beam L. Handled as individual. Thereby, it can respond, without setting the area of the light-receiving surface of the light receiving element 13 so that it may differ.

  Next, with reference to FIG. 7, signal processing of the received light signal in the above configuration will be described. For convenience of explanation, the light receiving elements a (k) in order from the upper end to the lower end of the light receiving elements 13 (1, k) to 13 (11, k) in each row of the explanation are sequentially described here. It is made to correspond. In the signal processing, since the laser light L is irradiated a plurality of times for each column, the light reception signal at that time is detected as a delay time from the emission timing of the laser light L.

  When each of the light receiving elements a to k receives the reflected light irradiated with the laser light L of the light emitting unit, it outputs a light reception signal. The signal processing circuit receives the light emission timing signal of the laser beam from the light emission control circuit, obtains a time difference from the light reception timing signal when the light reception signals by the light receiving elements a to k are input, and converts it into a digital signal. Thereby, the flight time (ToF) of the laser beam L is obtained.

  In the signal processing circuit, the light receiving elements a to c are group A, the light receiving elements d and e are group B, and the light receiving element f is group C. Similarly, light receiving elements g and h are group D, and light receiving elements i to k are group F. And the information of the flight time about each group AF is put together and a histogram is produced | generated. Thereafter, the signal processing circuit selects the most frequent time information based on each histogram, converts the time information into distance information, and calculates a distance value. In this way, the distance value can be calculated under the same light receiving condition by corresponding to each light receiving position by the number of light receiving elements corresponding to the light receiving intensity of the laser light L.

  Next, the method shown in FIG. 8 will be described. Instead of the signal processing shown in FIG. 7, in the signal processing circuit shown in FIG. 8, histogram generation processing is performed individually for each of the light receiving elements a to k in the signal processing circuit. Next, the signal processing circuit selects time information having the highest frequency from the histogram generation result, converts the time information into distance information, and calculates the distance value by collecting the results for each group. In this way, the distance value can be calculated under the same light receiving condition by corresponding to each light receiving position by the number of light receiving elements corresponding to the light receiving intensity of the laser light L.

  Therefore, according to the sixth embodiment, a plurality of light receiving elements 13 can be combined into a single one without adjusting the area of the light receiving portion of the light receiving element 13 so that the received light intensity of the laser light L is equal. By collecting signals as a light receiving element, the same effect as the fifth embodiment can be obtained.

  In the above-described embodiment, the light receiving elements 13 are arranged in a matrix. However, the present invention is not limited to this, and even when the light receiving elements 13 are arranged in a checkered pattern, the first element-free pixel is first described. By generating the light reception information by performing the interpolation processing as described in the second embodiment, the signal processing circuit can perform the signal processing in the same manner.

(Seventh embodiment)
FIGS. 9A and 9B show a seventh embodiment. In this embodiment, in each of the fifth and sixth embodiments, the laser light L of the light emitting unit is set to be a vertically long light for each column. The application example applicable to the case where it irradiates is shown.

In this embodiment, with respect to the light receiving signal of the element pixel in which the light receiving element 2 is arranged, the light receiving signal is captured corresponding to the irradiation range of the laser light L. In the first method shown in FIG. 9A, the irradiation range of the laser light L extends beyond the width of the column, and accordingly, the light receiving signal is received by the light receiving elements 2 in both adjacent columns. A signal is taken in. Here, for example, with respect to the element pixel A, in addition to the light reception signal a (0) of the light receiving element 2, as shown in the following equation (6), the light reception information a (1) of the light receiving elements 2 in the adjacent columns. ) And a (2) are also weighted and added.
Light reception signal A = a (0) + k1 × a (1) + k2 × a (2) (6)

Further, as shown in FIG. 9B, in consideration of the spread of the laser light L, the light receiving information of the light receiving element 2 in a wider range can be taken into the following equation (7).
Light reception signal A = a (0) + k1 × a (1) + k2 × a (2)
+ M1 * b (1) + m2 * b (2) + m3 * b (3) + m4 * b (4)
+ N1 * c (1) + n2 * c (2) (7)

According to the seventh embodiment as well, it is possible to obtain the same operational effects as those of the sixth embodiment, and it is possible to more efficiently detect light reception information corresponding to the spread of the laser light L.
Note that this embodiment can also be applied to a checkered arrangement including non-element pixels in which the light receiving element 2 is not arranged.

(Eighth embodiment)
FIG. 10 shows an eighth embodiment, which will be described below.
In this embodiment, instead of irradiating the laser beam L from the light emitting portion so as to spread in the vertical direction corresponding to the rows of the light receiving elements 2, the laser beam L is irradiated in an obliquely inclined state.
At this time, for example, as shown in FIG. 10B, the laser light L is irradiated in an inclined manner so that the light receiving element 2 corresponds in an oblique direction. In such irradiation with the laser light L, it is projected forward of the vehicle as shown in FIG. In this case, when a person P or the like is present in front, the probability that the part of the laser beam L projected obliquely is irradiated to the person P is high, and a person or an object can be detected quickly. become.

In the above-described embodiment, the inclination direction of the laser light L is set so as to correspond to the arrangement state of the light receiving element 2, but the present invention is not limited to this, and irradiation can be performed at an arbitrary inclination angle. In this case, a distance value can be obtained by obtaining a light reception signal by the corresponding light receiving element 2.
Further, in consideration of the spread of the laser light L, the light receiving information of the light receiving element that receives a part of the light due to the leakage of the laser light L can be used by using the principle as shown in the seventh embodiment. .

(Other embodiments)
In addition, this invention is not limited only to one embodiment mentioned above, It can apply to various embodiment in the range which does not deviate from the summary, For example, it can deform | transform or expand as follows. .

  In each of the above embodiments, an example is shown in which the present invention is applied to a laser radar that calculates the distance by irradiating a laser beam in front of the vehicle. However, the present invention is not limited to this, and the viewing angle is increased by increasing the number of pixels of the light receiving device. Can be applied. For example, the present invention can be applied to an image sensor of a camera.

  In the drawing, 1, 11, 11a are light receiving devices, 1a is a matrix arrangement area, 1b, 1c are checkered arrangement areas, 2, 12, 13 are light receiving elements, 2a is a light receiving section, 2b is a light receiving circuit, 3 is a control circuit ( Pixel information processing unit) 4 is a power line.

Claims (7)

A plurality of light receiving elements (2) including a light receiving portion (2a) and a light receiving circuit (2b) and two-dimensionally arranged in the arrangement region;
A power supply line (4) provided to feed power to the light receiving elements disposed in the first direction among the plurality of light receiving elements, and disposed at a position excluding at least the light receiving portion;
The light receiving device, wherein a checkered arrangement area (1b, 1c) in which at least a part of the plurality of light receiving elements of the plurality of light receiving elements are arranged in a checkered pattern is provided in the arrangement area. The light receiving device according to claim 1,
A pixel information processing unit (3) that generates pixel information from light reception information of the plurality of light receiving elements in the arrangement region;
The pixel information processing unit performs interpolation processing on a non-element pixel in which the light receiving element is not arranged in the checkered arrangement region based on pixel information of an element pixel in which the light receiving element located around the non-element pixel is arranged. To generate pixel information of the non-element pixel. The light receiving device according to claim 1,
The pixel information processing unit (3) classifies the light reception information obtained by receiving the light receiving element a plurality of times with respect to light projection under the same conditions for each of the plurality of light receiving elements into a plurality of levels. A light receiving signal of the highest level is generated as the pixel information of the element pixel;
For the non-element pixels in the checkered arrangement area, the light receiving signals of the light receiving elements located in the periphery are divided into a plurality of levels and added by multiplying by a weighting coefficient, and the light receiving signal having the highest appearance frequency is the pixel information. A light receiving device characterized by performing interpolation processing generated as follows. In the light-receiving device according to claim 2 or 3,
In the second and subsequent interpolation processes, the pixel information processing unit (3) multiplies pixel information of the surrounding elemental pixels and pixel information of the non-elemental pixels by a weighting coefficient, and generates new pixel information. And a light receiving device. A plurality of light receiving elements (2) including a light receiving portion (2a) and a light receiving circuit (2b) and two-dimensionally arranged in the arrangement region;
A power line (4) provided to feed power to the light receiving elements arranged in the first direction among the plurality of light receiving elements, and disposed at a position excluding at least the light receiving part;
A pixel information processing unit (3) that generates pixel information from light reception signals of the plurality of light receiving elements in the arrangement region;
When each of the plurality of light receiving elements has a distribution in which the intensity of light projection varies depending on a position, the pixel information processing unit generates a light reception signal for light projection under the same conditions when performing the interpolation process. A light receiving device that performs a corresponding weighting process. The light receiving device according to claim 5,
The plurality of light receiving elements (2) are provided so that the light receiving area of the light receiving portion corresponds to a light receiving signal for light projection under the same conditions, corresponding to the case where the light projection has a distribution with different intensities depending on positions. A light receiving device. The light receiving device according to claim 5,
The pixel information processing unit corresponds to a case where the light projection has a distribution with different intensities depending on positions, and the same condition is applied to the light receiving intensities that are weak with reference to the light receiving intensities of the plurality of light receiving elements being the strongest. A light receiving device, wherein a plurality of light receiving elements are provided as one light receiving element so as to handle the light received signals so as to correspond to light receiving signals for light projection in

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